In the past, most automotive light sources have involved the use of incandescent bulbs. While working well and being inexpensive, these bulbs have a relatively short life and, of course, the thin filament employed was always subject to breakage due to vibration.
Recently some of the uses, particularly the stoplight, have been replaced by LEDs. These solid-state light sources have incredible life times, in the area of 100,000 hours, and are not as subject to vibration failures. However, these LED sources have been hard-wired into their appropriate location, which increases the cost of installation. It would therefore be an advance in the art if an LED light source could be provided that had the ease of installation of the incandescent light sources. It would be a still further advance in the art if an LED light source could be provided that achieved an industry accepted interchangeable standard to replace the aforementioned incandescent bulb.
Such light sources have been developed and occasionally they have employed LEDs in combination with optical fibers or other light guides to concentrate the light of multiple LEDs or to spread the light in a desired fashion. One such light source is described in co-pending patent application Ser. No. 10/899,546, filed Dec. 20, 2004, and assigned to the assignee of the present invention. The latter light source uses a plurality of light guides, in a one-to-one relationship with a like plurality of LEDs. While the arrangement works well, it is expensive and requires a large number of parts, all of which require rather precise alignment.
It would be a further advance in the art if a light source could be developed using LEDs together with a simplified form of light guide.